1. Field of the Invention
This invention relates to a structure floating on a body of water. More particularly, the invention relates to a floating structure from which drilling or producing operations concerning oil and gas are carried out. In more specific aspects, the invention concerns a floating structure having buoyancy means for supporting the structure and anchored to an ocean floor by parallel elongated members such as riser pipes.
2. Setting of the Invention
In recent years there has been considerable attention attracted to the drilling and production of wells located in water. Wells may be drilled in the ocean floor from either fixed platform in relatively shallow water or from floating structures or vessels in deeper water. In deeper water, it is common practice to drill from a floating structure. In recent years, there has been attention directed toward many different kinds of floating structures from which underwater wells can be drilled. One such drilling structure is referred to as the Vertically Moored Platform and is described in U.S. Pat. No. 3,648,638, issued Mar. 14, 1972, Kenneth A. Blenkarn, inventor. In the Vertically Moored Platform, a structure is supported from the surface of the water by buoyant members. The buoyant members are connected to anchors in the floor of the body of water by elongated leg members which are parallel. These leg members are most commonly large diameter; e.g., 20 inches, and are called riser pipes.